Loading coil terminal



April 10, 1951 E. L. DROM 2,548,206

LOADING COIL TERMINAL Filed Dec. 20, 1946 2 Sheets-Sheet 1 fill [N708 EL. DRUM ATTOR/Vfy April 10, 1951 DROM 2,548,206

LOADING COIL TERMINAL Filed Dec. 20, 1946 2 Sheets-Sheet 2 IAN 17701?Patented Apr. 10, 1951 LOADING con. TERMINAL Edwin L. Drom, Brookfield,Ill., assignor to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Application December 20, 1946, Serial No.717,527

14 Claims.

This invention relates to electrical devices and more particularly toloading coils and associated terminal supports and to a method of makingthe same.

When connecting coils wound of fine wire into electrical circuits, it isnecessary to devise a means of connecting the fine wire electrically tothe relatively heavier connecting wires of a circuit without strainingthe fine wire or breaking it. In many types of mounted transformers andcoils the ends of the coils are soldered to permanent terminals securedto insulatin strips fastened to the coil mountings or to containers inwhich the coils are disposed.

In the manufacture of dowel-mounted toroidal loading coilassembliesdisclosed and claimed in the co-pending application of E. J.Crane and R. P. Cross, Jr., Serial No. 717,526, filed December 20, 1946,and which are to be used in splice loaded telephone cables, an importantconsideration is the reduction in the bulk of the loading unit that isto be sheathed in the cable. All the known practical methods of coil endconnection to telez around the block, the spaced-apart relation beingmaintained by the specially placed grooves in the block. The turn of thepair of wire is continued to permit the wires to again cross the surfaceof the washer in a definite spaced-apart relation after which anotherinsulating washer is placed directly over the first one, therebysandwiching the wires between, them. Heatand pressure are then appliedto form a solid Washer, having lead wires radiating therefrom.

A complete understanding of the invention may be had by reference to thefollowing detailed description taken in conjunction with the accom:

' panying drawings, in which phone lines involve the fastening of a coilend to a I terminal located on some type of terminal support and thensecuring the telephone line to the terminal, a time wasting processinvolving a bulky double connection on eachterminal.

Objects of this invention are to provide a new and efiicient terminalsupport and connection for electrical devices and a method of making thesame.

In accordance with one embodiment of this invention, a toroidal coil isprovided having a terminal support formed from a pair of fibrous washersimpregnated with a thermosetting insulating compound between whichwashers insulated wire leads are placed, the whole then being pressedtogether between hot plates so that the two washers will adhere to eachother trapping the wire leads therebetween. This forms a compositewasher having insulated wires radiating Fig. l is an illustration of adowel-mounted toroidal coil loading unit in which one embodiment of theinvention is used;

Fig. 2 is a sectional view of the loading coil unit shown in Fig. 1 andtaken on the line 22 of that figure;

Fig. 3 is a fragmentary sectional view of the loading coil unit taken onthe line 3-'-3 of Fig. 2 to illustrate in more detail the spacer andwasher arrangement between adjacent coils;

Fig. 4 is a cross sectional view of the fragmentary portion shown inFig. 3 and taken on the line 4-4 of Fig. 2;

Fig. 5 shows the spaced-apart portion of a "pair of telephone lines;

Fig. 6 is a plan view of the assembling fixture showing the first washerin place and the spacedapart portion of the telephone lines wrappedaround the assembling fixture; v

Fig. 7 is a front elevation of the fixture shown in Fig. 6 and showingin detail the grooves for guiding the wire;

Fig. 8 is a side elevation of the fixture shown in Fig. 6 showing thetwo washers with the conductors interposed therebetween beingconipressed between the fixture and the upper block; and

Fig. 9 shows the invention embodied in a terminal supporting washer.

As shown in the drawings -(Fig. 1) one embodiment of the inventioncomprises a terminal supporting washer 29 made of insulating material,which has embedded therein portions of four insulated electricalconductors 2|, 22, 23 and 24, which are cut from a pair of conductors 25and 26 (Fig. 5) as hereinafter described. One end of each conductor'iscut short near the periphery of the washer to form stub terminals 30,3!, 32 and 33 to which coil ends may be soldered. The combination ofthis terminal support and its associated toroidal coil is especiallyuseful in the construction of dowel-mounted toroidal loading coil unitsof a type shown generally at 3 (Fig. 1). Since these loading units areto be spliced and fitted directly into cables, it is imperative that allcomponents be as small and compact as possible to adequately control thebulk of the entire unit.

The loading unit 3 comprises a plurality of toroidal coils 35 wound onannular cores 36 and mounted on a dowel 45, each of said coils usuallyhaving two windings of relatively thin wire. The coils are separated byinsulating spacers H and iron washers 42 (Figs. 3 and 4). Each terminalsupporting washer 20 is spaced from its associated coil first by an ironwasher and then by an insulating spacer 4! between the iron washer 42and the coil 35. The ends 43 of the relatively thin coil windings aresoldered to the relatively heavy stub terminals 30, 3|, 32 and 33. Theother ends of the conductors 2!, 22, 23 and 24 are brought out at theends of the loading coil unit 34, as shown in Fig. 1.

The advantages of this terminal washer 29 are readily apparent. theconductors 2 l, 22, 23 and 24 will stand a substantial amount of abusewithout in any way aiTecting the connection between the stub terminalsand the ends of the coil windings which are of relatively thin wire.Another advantage is that the connecting' lead and the stub terminal arethe same conductor thus eliminating one connection and requiring onlythe soldered connection between the stub terminal and the coil end. Itwill be remembered that other types of terminals are originally separatefrom both the coil end and the lead thereto, both of which must besoldered to the terminal. another advantage is the flexibility of theterminal stub which is conducive to space saving.

Loading coils are usually provided with two windings to load both sidesof a telephone line, each coil being in series with one of the lines. Inconnectinga set of loading coils into line, it is obviously importantthat the lines be connected to the proper coil ends to prevent the coilsfrom being connected across the line instead of in series with the line.It is customary to colorcode lines for identification purposes. Forexmay be white and the insulation on the other line of the pair may bestriped. In order to load the lines, the white line is broken and onewinding of a loading coil is connected in series to the two open ends ofthe white line. The striped line is also cut and another coil connectedin series with the open ends of that line. It will be apparent that ifthe insulation on the conductors 23 and 2| of the washer 20 are white incolor it will greatly aid and facilitate the connection into the whitetelephone line of that winding of the loa ing coil which is connected toterminal stubs 30 and 33. The other two conductors 22 and 24 are stripedto aid in connecting into the striped line the coil winding that isconnected to the terminal stubs 3| and 32. The following method offorming a terminal supporting washer will ensure that the coil ends willbe connected to the proper terminal stubs.

A circular washer 44 made from a fibrous in sulating material andimpregnated with an insulating material, preferably a thermo-settingmaterial, is placed on a guide pin 45 mounted on the lower block Mi ofthe a sembling fixture 4?. which guide block has grooves 5i], 5!, 52,53, 54 and 55 formed in the top, and grooves 65 and 5! Still 4 4 alongtheir length with an acetate bonding ma terial, and which may becolor-coded white and white striped with red are spread apart for asubstantial distance intermediate their ends (Fig. 5) and are laidacross the washer 45 on the block 46 in the manner shown in Fig. 6 sothat a part of the bonded pair up to a point of divergence 62 lies inthe groove 56; The conductors begin to diverge at the rim of the washerM. and, passing over a portion of the washer, the individual conductorsare laid in the grooves 55 and 55, the white in groove 55 and thestriped in groove 54. The spread apart conductors are then wrappedaround the block 55, the white following and being disposed in thegroove 6! and the striped in the groove 50. As the conductors arebrought up around the other side of the block,

ample, the insulation on one line of a pair of lines ductors 25 and 26which may be bonded together the white is laid in the groove 5! and thestriped into groove 52, and both conductors are again laid across thewasher converging at a point 53 which is just outside the rim of thewasher M where the bonded pair of conductors are then laid in the groove53.

It will be seen that this method of locating the wire forces theoperator to maintain a definite spaced-apart relation and willinvariably end with the conductors lying in a predetermined requiredposition. Next, another washer 65 similar to washer 44 is placed on thepin 15 to form a sandwich with the conductors between the two washers.An upper block 65 of the assembly fixture 41 provided with spacers illand ll is placed over the washer and the whole assemblage is placedbetween the heated platens of a press (not shown) which are pressedtogether thereby forcing the blocks 56 and 65 together, the meeting ofthe blocks beinglimited by the spacers it and H. Sufiicient heat andpressure are applied to soften the impregnant in the washers to provideenough flow to encompass the conductors and form a composite moldedwasher having wires. radiating therefrom. The conductors are cut atpoints 12, l3, l4 and 15 and skinned to the rim of the washer therebyforming terminal stubs. The other ends of the conductors may be used tosplice the loading coils to the wires of a cable.

What is claimed is:

l. A terminal support for annular shaped electrical devices, saiddevices having a plurality of peripherally extending terminal leadscomprising an annular member made of insulating material of a diameterthe same as that of the device and a plurality of conductors embedded insaid member and extending from its peripheral edge, one end of each ofsaid conductors forming stub terminals for connection to the terminalleads of the device.

2. A terminal support for annular shaped electrical devices, saiddevices having a plurality of peripherally extending terminal leadscomprising a washer made of insulating material of a diameter the sameas that of the device and a plurality of conductors embedded in saidwasher and having their ends extending from the peripheral edge of thewasher for connection to the terminal leads of the device.

3. A terminal support for annular shaped electrical devices, saiddevices having a plurality of peripherally extending terminal leadscomprising a washer made of fibrous material impregnated with aninsulating compound of a diameter the same as that of the device and aplurality of conductors embedded in said washer and having their endsextending from the peripheral edge of the washer for c'onnectionto theterminal leads of the device.

4. A'termin'al support for annular shaped electrical devices, saiddevices having a plurality of peripherally extending terminal .leadscomprising an annular wafer made of insulating material, a secondannular wafer similar to and bonded to said first Wafer, said wafershaving diameters the same as that of the device, and a wire interposedbetween said wafers, the ends of said wire extending from the peripheraledges of said wafers for connection to the terminal leads of the=device.

5. A terminal supportforannular shaped'electrical devices, said deviceshaving a pluralit -of peripherally extending terminal :leads comprisinga washer made of insulating material, a second washer similar toand'bonded to said washer, said washers, having diameters the same asthat of the device, and a wire interposed between said washers, the endsof said wire extending from the peripheries of said Washers forconnection to the terminal leads of the device.

6. A terminating element fo an annular shaped loading coil, said coilhaving a plurality of peripherally extending terminal leads comprising apair of annular wafers of insulating material adhered one to the other,said wafers having diameters the same as that of the coil and a pai ofrelatively heavy wires out to form two pair of terminal ends placedbetween the wafers before they are adhered one to the other with theterminal ends extending from the peripheral edges of the wafers forconnection to the terminal leads of a loading coil and with the otheends of the pair of wires extending from the peripheral edges of thewafers for attachment to a line to be loaded.

7. A method of making a terminal support comprising placing a washermade of insulating material on a die block, winding a plurality ofspaced apart conductors around said die block and washer and inengagement with the washer while maintaining the conductors inspacedapart relation, maintaining the spaced apart relation for acomplete turn to form opposed loops, placing a second insulating washerdirectly over said first washer and on top of said conductors, forcingthe two washers together under sufficient heat and pressure to cause theinsulating material to flow and encompass said conductors to imbed themin the structure formed by the washers, and cutting the loops to form acomposite unit having conductors extending therefrom.

8. A method of forming a terminal support comprising laying a pluralityof conductors in spaced apart relation across a Washer formed frominsulating material and in engagement therewith, bringing said pluralityof conductors in a loop underneath said washer and in engagementtherewith all the while maintaining said spaced apart relation, turningsaid pair. of conductors upward and again laying them across said washerin a loop, placing another similar washer over said first washer tosandwich said conductors therebetween, compressing the assemblage at asufficient pressure and the necessary temperature to cause saidinsulating material to flow around said conductors to imbed them in thestructure formed by the washers, and cutting the loops to form acomposite washer having conductors extending therefrom.

9. A method of making a terminal mounting comprising separating for apredetermined portion along their length at a point intermediate oftheir ends a pair of insulated wires normally substantially joined alongtheir entire length thereby forming a spaced apart portion of saidpredeter- 'minedporti'on, placing lone end -.ofr:said=;spaced apartportion -on top "of a wafer formed from thermo-setting material in sucha way that one of the points of divergence of the wires lies at aboutthe periphery of said wafer the'wires diverging from this point acrossthe top of said wafer, wrapping said wires in a loop underneath saidwafer to'maintain a spaced apart relationship between the wires in theloop,'looping across the top of said washer the remaining end of saidspaced apart portion so that the wires converge across the top of saidwafer to a point at about the periphery of said wafer, placing anothersimilar wafer on top of the first wafer, the portion of the conductorslying across the top of the said first wafer thereby being interposedbetween said wafers, pressing said wafers together under sufficient heatand pressure'to cause said thermo-setting material to flow around saidconductors and to thermo-set and cutting the loops thereby forming. acomposite member having wires extending therefrom,

10. A method of making a terminal assembly for electrical devicescomprising spreading apart a pair of bonded conductors for apredetermined length intermediate of their ends, placing one end of thespread apart portion of said conductors on top of a thermo-settingsheet, bringing the conductors in a loop around the bottom ofsaid sheetwhile maintaining a spaced relation between said conductors in saidloop, looping the other end of said spread apart portion of, saidconductors across another portion of the top of said sheet, placinganother thermo-setting sheet over said first sheet so that theconductors will be interposed therebetween, pressing the two sheetstogether under suflicient heat and pressure to cause the material insaid sheets to flow around said conductors and to thermo-set and cuttingthe loops thereby forming a composite structure having conductorsleading therefrom.

11. The method of attaching paired conductors to an insulated terminalmounting which comprises providing a predetermined length of a pair ofconductors, separating the two conductors at a point intermediate theends of the length, placing them on top of a thermo-setting disc at thepoint where the pair of conductors diverge, maintaining a definitespacing between the conductors of the pair and looping them in spacedrelation around the bottom of the disc, looping a second length of thesame paired spaced apart conductors across and on top of anotherportionof the thermo-setting disc ad acent the point where they converge,applying sufiicient heat and pressure to coalesce the said discs withthe conductor portions therebetween, and cutting the loops to form acomposite disc with conductors extending therefrom.

12. A method of forming a terminal support comprising laying a pluralityof conductors in spaced apart relation across and in engagement with awafer of insulatin material, bringing said conductors in a loop undersaid wafer while maintaining them spaced apart and in engagement withthe wafer, again looping the conductors across the top of and inengagement with said wafer, placing a second wafer of the same shape asthe first wafer on the conductors on the first mentioned wafer, pressingthe wafers together to embed the conductors therein, adhering the waferstogether and cutting the loops.

13. A method of forming a terminal support comprising laying a pluralityof looped conductors inspaced apart relation across and in engagementwith a I wafer of insulating material, placing a second wafer of thesameshape as the first wafer on the conductors on the first mentionedwafer,

the looped portions of the conductors being ar- 5 ranged outside theperipheries of the washers, pressing the wafers together to embed theconductors therein, adhering the wafers together and cutting the loops.

14. A terminating element for toroidal coil windings comprising a washerhaving embedded therein a plurality of conductors, one end of each ofsaid conductors extending from the edge of said washer and beingconnected to the ends of the windings of said coil, the other ends ofsaid conductors extending from the edge of said washer for connection towires of a cable to be loaded.

EDWIN L. DROM.

a I REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS Number Name Date 1,099,480 Winter June 9, 191a1,289,941 Shaw et a1 Dec. 31, 1918 1,587,813 Young June 8, 19261,675,419 Myers July 3, 1928 2,014,399 Sprague Sept. 17, 1935 2,079,697Ranges May 11, 1937 FOREIGN PATENTS Number Country Date 861,229 FranceOct. 22, 1940

